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					                 CSS Tutorial
Save a lot of work with CSS!

In our CSS tutorial you will learn how to use CSS to control the style
and layout of multiple Web pages all at once.

CSS, short for Cascading Style Sheets, a new feature being added to
HTML that gives both Web site developers and users more control
over how pages are displayed. With CSS, designers and users can
create style sheets that define how different elements, such as
headers and links, appear. These Style Sheets can then be applied
to any Web page.

Cascading Style Sheets, level 2 (CSS2) is a style sheet language
that allows authors and users to attach style (eg, fonts, spacing, and
aural cues) to structured documents (eg, HTML documents and XML
applications). By separating the presentation style of documents
from the content of documents, CSS2 simplifies Web authoring and
site maintenance. CSS2 builds on CSS1 and, with very few
exceptions, all valid CSS1 style sheets are valid CSS2 style sheets.
...A method of coding that allows users to define how certain HTML,
DHTML, or XML structural elements, such as paragraphs and
headings, should be displayed using style rules instead of additional
markup.

CSS are used to design web pages. They are web pages derived
from multiple sources with a defined order of precedence where the
definitions of any style element conflict. CSS gives more control over
the appearance of a web page to the page creator than to the
browser designer or the viewer. Since it's likely that different
browsers will choose to implement CSS somewhat differently, the
web page creator must test the page with different browsers.
                     Lesson 1: Introduction to CSS
What You Should Already Know

Before you continue you should have some basic understanding of the following:

      HTML / XHTML

If you want to study this subject first, find the tutorials on our Home page.




What is CSS?

      CSS stands for Cascading Style Sheets
      Styles define how to display HTML elements
      Styles are normally stored in Style Sheets
      Styles were added to HTML 4.0 to solve a problem
      External Style Sheets can save you a lot of work
      External Style Sheets are stored in CSS files
      Multiple style definitions will cascade into one




CSS Demo

With CSS, your HTML documents can be displayed using different output styles:




Styles Solve a Common Problem

HTML tags were originally designed to define the content of a document. They were
supposed to say "This is a header", "This is a paragraph", "This is a table", by using
tags like <h1>, <p>, <table>, and so on. The layout of the document was supposed
to be taken care of by the browser, without using any formatting tags.

As the two major browsers - Netscape and Internet Explorer - continued to add new
HTML tags and attributes (like the <font> tag and the color attribute) to the original
HTML specification, it became more and more difficult to create Web sites where the
content of HTML documents was clearly separated from the document's presentation
layout.

To solve this problem, the World Wide Web Consortium (W3C) - the non profit,
standard setting consortium, responsible for standardizing HTML - created STYLES in
addition to HTML 4.0.

All major browsers support Cascading Style Sheets.
Style Sheets Can Save a Lot of Work

Styles sheets define HOW HTML elements are to be displayed, just like the font tag
and the color attribute in HTML 3.2. Styles are normally saved in external .css files.
External style sheets enable you to change the appearance and layout of all the
pages in your Web, just by editing one single CSS document!

CSS is a breakthrough in Web design because it allows developers to control the
style and layout of multiple Web pages all at once. As a Web developer you can
define a style for each HTML element and apply it to as many Web pages as you
want. To make a global change, simply change the style, and all elements in the Web
are updated automatically.




Multiple Styles Will Cascade Into One

Style sheets allow style information to be specified in many ways. Styles can be
specified inside a single HTML element, inside the <head> element of an HTML page,
or in an external CSS file. Even multiple external style sheets can be referenced
inside a single HTML document.

Cascading Order

What style will be used when there is more than one style specified for an
HTML element?

Generally speaking we can say that all the styles will "cascade" into a new "virtual"
style sheet by the following rules, where number four has the highest priority:

   1.   Browser default
   2.   External style sheet
   3.   Internal style sheet (inside the <head> tag)
   4.   Inline style (inside an HTML element)

So, an inline style (inside an HTML element) has the highest priority, which means
that it will override a style declared inside the <head> tag, in an external style
sheet, or in a browser (a default value).
                             Lesson 2: CSS Syntax
Syntax

The CSS syntax is made up of three parts: a selector, a property and a value:

selector {property: value}

The selector is normally the HTML element/tag you wish to define, the property is
the attribute you wish to change, and each property can take a value. The property
and value are separated by a colon, and surrounded by curly braces:

body {color: black}

Note: If the value is multiple words, put quotes around the value:

p {font-family: "sans serif"}

Note: If you wish to specify more than one property, you must separate each
property with a semicolon. The example below shows how to define a center aligned
paragraph, with a red text color:

p {text-align:center;color:red}

To make the style definitions more readable, you can describe one property on each
line, like this:

p
{
text-align: center;
color: black;
font-family: arial
}




Grouping

You can group selectors. Separate each selector with a comma. In the example
below we have grouped all the header elements. All header elements will be
displayed in green text color:

h1,h2,h3,h4,h5,h6
{
color: green
}
The class Selector

With the class selector you can define different styles for the same type of HTML
element.

Say that you would like to have two types of paragraphs in your document: one
right-aligned paragraph, and one center-aligned paragraph. Here is how you can do
it with styles:

p.right {text-align: right}
p.center {text-align: center}

You have to use the class attribute in your HTML document:

<p class="right">
This paragraph will be right-aligned.
</p>
<p class="center">
This paragraph will be center-aligned.
</p>

Note: Only one class attribute can be specified per HTML element! The example
below is wrong:

<p class="right" class="center">
This is a paragraph.
</p>

You can also omit the tag name in the selector to define a style that will be used by
all HTML elements that have a certain class. In the example below, all HTML
elements with class="center" will be center-aligned:

.center {text-align: center}

In the code below both the h1 element and the p element have class="center". This
means that both elements will follow the rules in the ".center" selector:

<h1 class="center">
This heading will be center-aligned
</h1>
<p class="center">
This paragraph will also be center-aligned.
</p>

Do NOT start a class name with a number! It will not work in Mozilla/Firefox.
The id Selector

You can also define styles for HTML elements with the id selector. The id selector is
defined as a #.

The style rule below will match the element that has an id attribute with a value of
"green":

#green {color: green}

The style rule below will match the p element that has an id with a value of "para1":

p#para1
{
text-align: center;
color: red
}




Do NOT start an ID name with a number! It will not work in Mozilla/Firefox.



CSS Comments

Comments are used to explain your code, and may help you when you edit the
source code at a later date. A comment will be ignored by browsers. A CSS comment
begins with "/*", and ends with "*/", like this:

/* This is a comment */
p
{
text-align: center;
/* This is another comment */
color: black;
font-family: arial
}
                               Lesson 3: CSS How To...
Examples

     Look at Example 1

      <html>

      <head>


      <link rel="stylesheet"


      type="text/css" href="ex1.css" />


      </head>


      <body>


      <h1>This header is 36 pt</h1>


      <h2>This header is blue</h2>


      <p>This paragraph has a left


      margin of 50 pixels</p>


      </body>


      </html>


     Look at Example 2


      <html>


      <head>


      <link rel="stylesheet" type="text/css"


      href="ex2.css" />


      </head>


      <body>


      <h1>This is a header 1</h1>


      <hr>


      <p>You can see that the style


      sheet formats the text</p>


      <p><a href="http://www.microsoft.com"
       target="_blank">This is a link</a></p>


       </body>


       </html>




How to Insert a Style Sheet

When a browser reads a style sheet, it will format the document according to it.
There are three ways of inserting a style sheet:

External Style Sheet

An external style sheet is ideal when the style is applied to many pages. With an
external style sheet, you can change the look of an entire Web site by changing one
file. Each page must link to the style sheet using the <link> tag. The <link> tag
goes inside the head section:

<head>
<link rel="stylesheet" type="text/css"
href="mystyle.css" />
</head>

The browser will read the style definitions from the file mystyle.css, and format the
document according to it.

An external style sheet can be written in any text editor. The file should not contain
any html tags. Your style sheet should be saved with a .css extension. An example of
a style sheet file is shown below:

hr {color: sienna}
p {margin-left: 20px}
body {background-image: url("images/back40.gif")}
 Do NOT leave spaces between the property value and the units! If you use "margin-
left: 20 px" instead of "margin-left: 20px" it will only work properly in IE6 but it will
not work in Mozilla/Firefox or Netscape.

Internal Style Sheet

An internal style sheet should be used when a single document has a unique style.
You define internal styles in the head section by using the <style> tag, like this:

<head>
<style type="text/css">
hr {color: sienna}
p {margin-left: 20px}
body {background-image: url("images/back40.gif")}
</style>
</head>

The browser will now read the style definitions, and format the document according
to it.

Note: A browser normally ignores unknown tags. This means that an old browser
that does not support styles, will ignore the <style> tag, but the content of the
<style> tag will be displayed on the page. It is possible to prevent an old browser
from displaying the content by hiding it in the HTML comment element:

<head>
<style type="text/css">
<!--
hr {color: sienna}
p {margin-left: 20px}
body {background-image: url("images/back40.gif")}
-->
</style>
</head>

Inline Styles

An inline style loses many of the advantages of style sheets by mixing content with
presentation. Use this method sparingly, such as when a style is to be applied to a
single occurrence of an element.

To use inline styles you use the style attribute in the relevant tag. The style attribute
can contain any CSS property. The example shows how to change the color and the
left margin of a paragraph:

<p style="color: sienna; margin-left: 20px">
This is a paragraph
</p>



Multiple Style Sheets

If some properties have been set for the same selector in different style sheets, the
values will be inherited from the more specific style sheet.

For example, an external style sheet has these properties for the h3 selector:

h3
{
color: red;
text-align: left;
font-size: 8pt
}
And an internal style sheet has these properties for the h3 selector:

h3
{
text-align: right;
font-size: 20pt
}

If the page with the internal style sheet also links to the external style sheet the
properties for h3 will be:

color: red;
text-align: right;
font-size: 20pt

The color is inherited from the external style sheet and the text-alignment and the
font-size is replaced by the internal style sheet.




                       Lesson 4: CSS Background
The CSS background properties define the background effects of an element.




CSS Background Properties

The CSS background properties allow you to control the background color of an
element, set an image as the background, repeat a background image vertically or
horizontally, and position an image on a page.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property              Description                Values                 IE F    N W3C
background            A shorthand property for   background-color    4      1   6      1
                      setting all background     background-image
                      properties in one          background-repeat
                      declaration                background-
                                                 attachment
                                                 background-position
background-           Sets whether a              scroll              4    1   6   1
attachment            background image is         fixed
                      fixed or scrolls with the
                      rest of the page
background-color      Sets the background         color-rgb           4    1   4   1
                      color of an element         color-hex
                                                  color-name
                                                  transparent
background-image      Sets an image as the        url                 4    1   4   1
                      background                  none
background-position Sets the starting        top left                 4    1   6   1
                    position of a background top center
                    image                    top right
                                             center left
                                             center center
                                             center right
                                             bottom left
                                             bottom center
                                             bottom right
                                             x-% y-%
                                             x-pos y-pos
background-repeat     Sets if/how a               repeat              4    1   4   1
                      background image will       repeat-x
                      be repeated                 repeat-y
                                                  no-repeat




                             Lesson 5: CSS Text
The CSS text properties define the appearance of text.




CSS Text Properties

The CSS text properties allow you to control the appearance of text. It is possible to
change the color of a text, increase or decrease the space between characters in a
text, align a text, decorate a text, indent the first line in a text, and more.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).
Property              Description                  Values          IE F    N W3C
color                 Sets the color of a text     color           3   1   4   1
direction             Sets the text direction      ltr             6   1   6   2
                                                   rtl
letter-spacing        Increase or decrease the normal              4   1   6   1
                      space between            length
                      characters
text-align            Aligns the text in an        left            4   1   4   1
                      element                      right
                                                   center
                                                   justify
text-decoration       Adds decoration to text      none            4   1   4   1
                                                   underline
                                                   overline
                                                   line-through
                                                   blink
text-indent           Indents the first line of    length          4   1   4   1
                      text in an element           %
text-shadow                                        none
                                                   color
                                                   length
text-transform        Controls the letters in      none            4   1   4   1
                      an element                   capitalize
                                                   uppercase
                                                   lowercase
unicode-bidi                                       normal          5           2
                                                   embed
                                                   bidi-override
white-space           Sets how white space         normal          5   1   4   1
                      inside an element is         pre
                      handled                      nowrap
word-spacing          Increase or decrease the normal              6   1   6   1
                      space between words      length




                             Lesson 6: CSS Font
The CSS font properties define the font in text.
CSS Font Properties

The CSS font properties allow you to change the font family, boldness, size, and the
style of a text.

Note: In CSS1 fonts are identified by a font name. If a browser does not support the
specified font, it will use a default font.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property             Description                Values               IE F     N W3C
font                 A shorthand property for   font-style            4   1   4   1
                     setting all of the         font-variant
                     properties for a font in   font-weight
                     one declaration            font-size/line-height
                                                font-family
                                                caption
                                                icon
                                                menu
                                                message-box
                                                small-caption
                                                status-bar
font-family          A prioritized list of font family-name          3    1   4   1
                     family names and/or        generic-family
                     generic family names for
                     an element
font-size            Sets the size of a font    xx-small             3    1   4   1
                                                x-small
                                                small
                                                medium
                                                large
                                                x-large
                                                xx-large
                                                smaller
                                                larger
                                                length
                                                %
font-size-adjust     Specifies an aspect        none                 -    -   -   2
                     value for an element       number
                     that will preserve the x-
                     height of the first-choice
                     font
font-stretch         Condenses or expands       normal               -    -   -   2
                     the current font-family    wider
                                                narrower
                                                ultra-condensed
                                                extra-condensed
                                                condensed
                                                semi-condensed
                                                semi-expanded
                                                expanded
                                                extra-expanded
                                                ultra-expanded
font-style           Sets the style of the font normal                4   1   4   1
                                                italic
                                                oblique
font-variant         Displays text in a small- normal                 4   1   6   1
                     caps font or a normal     small-caps
                     font
font-weight          Sets the weight of a font normal                 4   1   4   1
                                               bold
                                               bolder
                                               lighter
                                               100
                                               200
                                               300
                                               400
                                               500
                                               600
                                               700
                                               800
                                               900




                           Lesson 7: CSS Border
The CSS border properties define the borders around an element.




CSS Border Properties

The CSS border properties allow you to specify the style and color of an element's
border. In HTML we use tables to create borders around a text, but with the CSS
border properties we can create borders with nice effects, and it can be applied to
any element.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.
W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property             Description                  Values           IE F    N W3C
border               A shorthand property for border-width         4   1   4   1
                     setting all of the       border-style
                     properties for the four  border-color
                     borders in one
                     declaration
border-bottom        A shorthand property for border-bottom-       4   1   6   1
                     setting all of the       width
                     properties for the       border-style
                     bottom border in one     border-color
                     declaration
border-bottom-color Sets the color of the         border-color     4   1   6   2
                    bottom border
border-bottom-style Sets the style of the         border-style     4   1   6   2
                    bottom border
border-bottom-       Sets the width of the        thin             4   1   4   1
width                bottom border                medium
                                                  thick
                                                  length
border-color         Sets the color of the        color            4   1   6   1
                     four borders, can have
                     from one to four colors
border-left          A shorthand property for border-left-width    4   1   6   1
                     setting all of the       border-style
                     properties for the left  border-color
                     border in one
                     declaration
border-left-color    Sets the color of the left border-color       4   1   6   2
                     border
border-left-style    Sets the style of the left   border-style     4   1   6   2
                     border
border-left-width    Sets the width of the left thin               4   1   4   1
                     border                     medium
                                                thick
                                                length
border-right         A shorthand property for border-right-width   4   1   6   1
                     setting all of the       border-style
                     properties for the right border-color
                     border in one
                     declaration
border-right-color   Sets the color of the        border-color     4   1   6   2
                     right border
border-right-style   Sets the style of the        border-style     4   1   6   2
                     right border
border-right-width   Sets the width of the       thin            4   1   4   1
                     right border                medium
                                                 thick
                                                 length
border-style         Sets the style of the       none            4   1   6   1
                     four borders, can have      hidden
                     from one to four styles     dotted
                                                 dashed
                                                 solid
                                                 double
                                                 groove
                                                 ridge
                                                 inset
                                                 outset
border-top           A shorthand property for border-top-width   4   1   6   1
                     setting all of the       border-style
                     properties for the top   border-color
                     border in one
                     declaration
border-top-color     Sets the color of the top border-color      4   1   6   2
                     border
border-top-style     Sets the style of the top   border-style    4   1   6   2
                     border
border-top-width     Sets the width of the top thin              4   1   4   1
                     border                    medium
                                               thick
                                               length
border-width         A shorthand property for    thin            4   1   4   1
                     setting the width of the    medium
                     four borders in one         thick
                     declaration, can have       length
                     from one to four values




                          Lesson 8: CSS Margin
The CSS margin properties define the space around elements.




CSS Margin Properties
The CSS margin properties define the space around elements. It is possible to use
negative values to overlap content. The top, right, bottom, and left margin can be
changed independently using separate properties. A shorthand margin property can
also be used to change all of the margins at once.

Note: Netscape and IE give the body tag a default margin of 8px. Opera does not!
Instead, Opera applies a default padding of 8px, so if one wants to adjust the margin
for an entire page and have it display correctly in Opera, the body padding must be
set as well!

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property             Description                Values               IE F    N W3C
margin               A shorthand property for margin-top             4   1   4   1
                     setting the margin       margin-right
                     properties in one        margin-bottom
                     declaration              margin-left
margin-bottom        Sets the bottom margin     auto                 4   1   4   1
                     of an element              length
                                                %
margin-left          Sets the left margin of    auto                 3   1   4   1
                     an element                 length
                                                %
margin-right         Sets the right margin of   auto                 3   1   4   1
                     an element                 length
                                                %
margin-top           Sets the top margin of     auto                 3   1   4   1
                     an element                 length
                                                %
                          Lesson 9: CSS Padding
The CSS padding properties define the space between the element border and the
element content.




CSS Padding Properties

The CSS padding properties define the space between the element border and the
element content. Negative values are not allowed. The top, right, bottom, and left
padding can be changed independently using separate properties. A shorthand
padding property is also created to control multiple sides at once.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property              Description                Values              IE F    N W3C
padding               A shorthand property for padding-top           4   1   4    1
                      setting all of the       padding-right
                      padding properties in    padding-bottom
                      one declaration          padding-left
padding-bottom        Sets the bottom padding length                 4   1   4    1
                      of an element           %
padding-left          Sets the left padding of   length              4   1   4    1
                      an element                 %
padding-right         Sets the right padding     length              4   1   4    1
                      of an element              %
padding-top           Sets the top padding of    length              4   1   4    1
                      an element                 %




                            Lesson 10: CSS List
The CSS list properties allow you to place the list-item marker, change between
different list-item markers, or set an image as the list-item marker.




CSS List Properties
The CSS list properties allow you to place the list-item marker, change between
different list-item markers, or set an image as the list-item marker.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property              Description                Values              IE F    N W3C
list-style            A shorthand property for list-style-type       4   1   6    1
                      setting all of the       list-style-position
                      properties for a list in list-style-image
                      one declaration
list-style-image      Sets an image as the       none                4   1   6    1
                      list-item marker           url
list-style-position   Sets where the list-item   inside              4   1   6    1
                      marker is placed in the    outside
                      list
list-style-type       Sets the type of the list- none                4   1   4    1
                      item marker                disc
                                                 circle
                                                 square
                                                 decimal
                                                 decimal-leading-
                                                 zero
                                                 lower-roman
                                                 upper-roman
                                                 lower-alpha
                                                 upper-alpha
                                                 lower-greek
                                                 lower-latin
                                                 upper-latin
                                                 hebrew
                                                 armenian
                                                 georgian
                                                 cjk-ideographic
                                                 hiragana
                                                 katakana
                                                 hiragana-iroha
                                                 katakana-iroha
marker-offset                                    auto                    1   7    2
                                                 length
                      Lesson 11: CSS Dimension
The CSS dimension properties allow you to control the height and width of an
element. It also allows you to increase the space between two lines.




CSS Dimension Properties

The CSS dimension properties allow you to control the height and width of an
element. It also allows you to increase the space between two lines.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property             Description              Values               IE F     N W3C
height               Sets the height of an    auto                 4    1   6   1
                     element                  length
                                              %
line-height          Sets the distance        normal               4    1   4   1
                     between lines            number
                                              length
                                              %
max-height           Sets the maximum         none                 -    1   6   2
                     height of an element     length
                                              %
max-width            Sets the maximum         none                 -    1   6   2
                     width of an element      length
                                              %
min-height           Sets the minimum         length               -    1   6   2
                     height of an element     %
min-width            Sets the minimum width length                 -    1   6   2
                     of an element          %
width                Sets the width of an     auto                 4    1   4   1
                     element                  %
                                              length
                    Lesson 12: CSS Classification
The CSS classification properties allow you to specify how and where to display an
element.




CSS Classification Properties

The CSS classification properties allow you to control how to display an element, set
where an image will appear in another element, position an element relative to its
normal position, position an element using an absolute value, and how to control the
visibility of an element.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property             Description               Values                IE F    N W3C
clear                Sets the sides of an      left                  4   1   4   1
                     element where other       right
                     floating elements are     both
                     not allowed               none
cursor               Specifies the type of     url                   4   1   6   2
                     cursor to be displayed    auto
                                               crosshair
                                               default
                                               pointer
                                               move
                                               e-resize
                                               ne-resize
                                               nw-resize
                                               n-resize
                                               se-resize
                                               sw-resize
                                               s-resize
                                               w-resize
                                               text
                                               wait
                                               help
display              Sets how/if an element    none                  4   1   4   1
                     is displayed              inline
                                               block
                                               list-item
                                               run-in
                                               compact
                                               marker
                                               table
                                                  inline-table
                                                  table-row-group
                                                  table-header-group
                                                  table-footer-group
                                                  table-row
                                                  table-column-group
                                                  table-column
                                                  table-cell
                                                  table-caption
float                Sets where an image or       left                 4   1   4   1
                     a text will appear in        right
                     another element              none
position             Places an element in a       static               4   1   4   2
                     static, relative, absolute   relative
                     or fixed position            absolute
                                                  fixed
visibility           Sets if an element           visible              4   1   6   2
                     should be visible or         hidden
                     invisible                    collapse




                      Lesson 13: CSS Positioning
The CSS positioning properties allows you to position an element.




CSS Positioning Properties

The CSS positioning properties allow you to specify the left, right, top, and bottom
position of an element. It also allows you to set the shape of an element, place an
element behind another, and to specify what should happen when an element's
content is too big to fit in a specified area.

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Property             Description                  Values               IE F    N W3C
bottom               Sets how far the bottom auto                      5   1   6   2
                     edge of an element is   %
                     above/below the bottom length
                 edge of the parent
                 element
clip             Sets the shape of an     shape          4   1   6   2
                 element. The element is auto
                 clipped into this shape,
                 and displayed
left             Sets how far the left      auto         4   1   4   2
                 edge of an element is to %
                 the right/left of the left length
                 edge of the parent
                 element
overflow         Sets what happens if the visible        4   1   6   2
                 content of an element    hidden
                 overflow its area        scroll
                                          auto
position         Places an element in a       static     4   1   4   2
                 static, relative, absolute   relative
                 or fixed position            absolute
                                              fixed
right            Sets how far the right      auto        5   1   6   2
                 edge of an element is to %
                 the left/right of the right length
                 edge of the parent
                 element
top              Sets how far the top         auto       4   1   4   2
                 edge of an element is        %
                 above/below the top          length
                 edge of the parent
                 element
vertical-align   Sets the vertical       baseline        4   1   4   1
                 alignment of an element sub
                                         super
                                         top
                                         text-top
                                         middle
                                         bottom
                                         text-bottom
                                         length
                                         %
z-index          Sets the stack order of      auto       4   1   6   2
                 an element                   number
                   Lesson 14: CSS Pseudo-classes
CSS pseudo-classes are used to add special effects to some selectors.

Syntax

The syntax of pseudo-classes:

selector:pseudo-class {property: value}

CSS classes can also be used with pseudo-classes:

selector.class:pseudo-class {property: value}




Anchor Pseudo-classes

A link that is active, visited, unvisited, or when you mouse over a link can all be
displayed in different ways in a CSS-supporting browser:

a:link {color: #FF0000}   /* unvisited link */
a:visited {color: #00FF00} /* visited link */
a:hover {color: #FF00FF} /* mouse over link */
a:active {color: #0000FF} /* selected link */

Note: a:hover MUST come after a:link and a:visited in the CSS definition in order to
be effective!!

Note: a:active MUST come after a:hover in the CSS definition in order to be
effective!!

Note: Pseudo-class names are not case-sensitive.




Pseudo-classes and CSS Classes

Pseudo-classes can be combined with CSS classes:

a.red:visited {color: #FF0000}
<a class="red" href="css_syntax.asp">CSS Syntax</a>

If the link in the example above has been visited, it will be displayed in red.
CSS2 - The :first-child Pseudo-class

The :first-child pseudo-class matches a specified element that is the first child of
another element.

In this example, the selector matches any p element that is the first child of a
div element, and indents the first paragraph inside a div element:

div > p:first-child
{
text-indent:25px
}

This selector will match the first paragraph inside the div in the following HTML:

<div>
<p>
First paragraph in div.
This paragraph will be indented.
</p>
<p>
Second paragraph in div.
This paragraph will not be indented.
</p>
</div>

but it will not match the paragraph in this HTML:

<div>
<h1>Header</h1>
<p>
The first paragraph inside the div.
This paragraph will not be indented.
</p>
</div>




In this example, the selector matches any em element that is the first child of a
p element, and sets the font-weight to bold for the first em inside a p element:

p:first-child em
{
font-weight:bold
}

For example, the em in the HTML below is the first child of the paragraph:

<p>I am a <em>strong</em> man.</p>
In this example, the selector matches any a element that is the first child of any
element, and sets the text-decoration to none:

a:first-child
{
text-decoration:none
}

For example, the first a in the HTML below is the first child of the paragraph and will
not be underlined. But the second a in the paragraph is not the first child of the
paragraph and will be underlined:

<p>
Visit <a href="http://www.w3schools.com">W3Schools</a>
and learn CSS!
Visit <a href="http://www.w3schools.com">W3Schools</a>
and learn HTML!
</p>




CSS2 - The :lang Pseudo-class

The :lang pseudo-class allows you to define special rules for different languages. In
the example below, the :lang class defines the type of quotation marks for q
elements with a lang attribute with a value of "no":

<html>
<head>
<style type="text/css">
q:lang(no)
{
quotes: "~" "~"
}
</style>
</head>
<body>
<p>Some text <q lang="no">A quote in a paragraph</q>
Some text.</p>
</body>
</html>




Pseudo-classes
Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Pseudo-class          Purpose                                           IE F     N W3C
:active               Adds special style to an activated element        4    1   8   1
:focus                Adds special style to an element while the        -    -   -   2
                      element has focus
:hover                Adds special style to an element when you         4    1   7   1
                      mouse over it
:link                 Adds special style to an unvisited link           3    1   4   1
:visited              Adds special style to a visited link              3    1   4   1
:first-child          Adds special style to an element that is the           1   7   2
                      first child of some other element
:lang                 Allows the author to specify a language to use         1   8   2
                      in a specified element




                  Lesson 15: CSS Pseudo-elements
CSS pseudo-elements are used to add special effects to some selectors.




Syntax

The syntax of pseudo-elements:

selector:pseudo-element {property: value}

CSS classes can also be used with pseudo-elements:

selector.class:pseudo-element {property: value}



The :first-line Pseudo-element

The "first-line" pseudo-element is used to add special styles to the first line of the
text in a selector:
p {font-size: 12pt}
p:first-line {color: #0000FF; font-variant: small-caps}
<p>Some text that ends up on two or more lines</p>

The output could be something like this:

SOME TEXT THAT ENDS
up on two or more lines

In the example above the browser displays the first line formatted according to the
"first-line" pseudo element. Where the browser breaks the line depends on the size
of the browser window.

Note: The "first-line" pseudo-element can only be used with block-level elements.

Note: The following properties apply to the "first-line" pseudo-element:

      font properties
      color properties
      background properties
      word-spacing
      letter-spacing
      text-decoration
      vertical-align
      text-transform
      line-height
      clear




The :first-letter Pseudo-element

The "first-letter" pseudo-element is used to add special style to the first letter of the
text in a selector:

p {font-size: 12pt}
p:first-letter {font-size: 200%; float: left}
<p>The first words of an article.</p>

The output could be something like this:

___
 | he first
 | words of an
article.

Note: The "first-letter" pseudo-element can only be used with block-level elements.

Note: The following properties apply to the "first-letter" pseudo- element:
      font properties
      color properties
      background properties
      margin properties
      padding properties
      border properties
      text-decoration
      vertical-align (only if 'float' is 'none')
      text-transform
      line-height
      float
      clear




Pseudo-elements and CSS Classes

Pseudo-elements can be combined with CSS classes:

p.article:first-letter {color: #FF0000}
<p class="article">A paragraph in an article</p>

The example above will make the first letter of all paragraphs with class="article"
red.




Multiple Pseudo-elements

Several pseudo-elements can be combined:

p {font-size: 12pt}
p:first-letter {color: #FF0000; font-size: 200%}
p:first-line {color: #0000FF}
<p>The first words of an article</p>

The output could be something like this:

___
 | he first
 | words of an
article.

In the example above the first letter of the paragraph will be red with a font size of
24pt. The rest of the first line would be blue while the rest of the paragraph would be
the default color.
CSS2 - The :before Pseudo-element

The ":before" pseudo-element can be used to insert some content before an
element.

The style below will play a sound before each occurrence of a header one element.

h1:before
{
content: url(beep.wav)
}




CSS2 - The :after Pseudo-element

The ":after" pseudo-element can be used to insert some content after an element.

The style below will play a sound after each occurrence of a header one element.

h1:after
{
content: url(beep.wav)
}




Pseudo-elements

Browser support: IE: Internet Explorer, F: Firefox, N: Netscape.

W3C: The number in the "W3C" column indicates in which CSS recommendation the
property is defined (CSS1 or CSS2).


Pseudo-element       Purpose                                            IE F    N W3C
:first-letter        Adds special style to the first letter of a text   5   1   8 1
:first-line          Adds special style to the first line of a text     5   1   8 1
:before              Inserts some content before an element                 1.5 8 2
:after               Inserts some content after an element                  1.5 8 2
                     Lesson 16: CSS2 Media Types
Media Types allow you to specify how documents will be presented in different
media. The document can be displayed differently on the screen, on the paper, with
an aural browser, etc.




Media Types

Some CSS properties are only designed for a certain media. For example the "voice-
family" property is designed for aural user agents. Some other properties can be
used for different media types. For example, the "font-size" property can be used for
both screen and print media, but perhaps with different values. A document usually
needs a larger font-size on a screen than on paper, and sans-serif fonts are easier to
read on the screen, while serif fonts are easier to read on paper.




The @media Rule

The @media rule allows different style rules for different media in the same style
sheet.

The style in the example below tells the browser to display a 14 pixels Verdana font
on the screen. But if the page is printed, it will be in a 10 pixels Times font. Notice
that the font-weight is set to bold, both on screen and on paper:

<html>
<head>
<style>
@media screen
{
p.test {font-family:verdana,sans-serif; font-size:14px}
}

@media print
{
p.test {font-family:times,serif; font-size:10px}
}
@media screen,print
{
p.test {font-weight:bold}
}
</style>
</head>
<body>
....
</body>
</html>
See it yourself ! If you are using Mozilla/Firefox or IE 5+ and print this page, you
will see that the paragraph under "Media Types" will be displayed in another font,
and have a smaller font size than the rest of the text.




Different Media Types

Note: The media type names are not case-sensitive.


Media Type       Description
all              Used for all media type devices
aural            Used for speech and sound synthesizers
braille          Used for braille tactile feedback devices
embossed         Used for paged braille printers
handheld         Used for small or handheld devices
print            Used for printers
projection       Used for projected presentations, like slides
screen           Used for computer screens
tty              Used for media using a fixed-pitch character grid, like teletypes and
                 terminals
tv               Used for television-type devices




          Lesson 17: You Have Learned CSS, Now What?
CSS Summary

This tutorial has taught you how to create style sheets to control the style and layout
of multiple web sites at once.

You have learned how to use CSS to add backgrounds, format text, add and format
borders, and specify padding and margins of elements.

You have also learned how to position an element, control the visibility and size of an
element, set the shape of an element, place an element behind another, and to add
special effects to some selectors, like links.

For more information on CSS, please take a look at our CSS examples and our CSS
reference.
Now You Know CSS, What's Next?

The next step is to learn XHTML and JavaScript.

XHTML

XHTML is the "new" HTML. The latest HTML recommendation is HTML 4.01. This is
the last and final HTML version.

HTML will be replaced by XHTML, which is a stricter and cleaner version of HTML.



JavaScript

JavaScript can make your web site more dynamic.

A static web site is nice when you just want to show flat content, but a dynamic web
site can react to events and allow user interaction.

JavaScript is the most popular scripting language on the internet and it works with
all major browsers.

If you want to learn more about JavaScript, please visit our JavaScript tutorial.




                       Lesson 18: CSS Examples
Background

Set the background color
<html>
<head>

<style type="text/css">
body {background-color: yellow}
h1 {background-color: #00ff00}
h2 {background-color: transparent}
p {background-color: rgb(250,0,255)}
</style>

</head>
<body>

<h1>This is header 1</h1>
<h2>This is header 2</h2>
<p>This is a paragraph</p>

</body>
</html>


Set an image as the background
<html>
<head>

<style type="text/css">
body
{
background-image:
url('bgdesert.jpg')
}
</style>

</head>

<body>
</body>

</html>


All the background properties in one declaration
<html>
<head>
<style type="text/css">
body
{
background: #00ff00 url('smiley.gif') no-repeat fixed center;
}
</style>
</head>

<body>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This   is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
<p>This is   some   text</p>
</body>

</html>




Text

Set the color of the text
<html>

<head>
<style type="text/css">
h1 {color: #00ff00}
h2 {color: #dda0dd}
p {color: rgb(0,0,255)}
</style>
</head>

<body>
<h1>This is header 1</h1>
<h2>This is header 2</h2>
<p>This is a paragraph</p>
</body>

</html>


Decorate the text
<html>
<head>
<style type="text/css">
h1 {text-decoration: overline}
h2 {text-decoration: line-through}
h3 {text-decoration: underline}
a {text-decoration: none}
</style>
</head>

<body>
<h1>This is header 1</h1>
<h2>This is header 2</h2>
<h3>This is header 3</h3>
<p><a href="http://www.w3schools.com/default.asp">This is a link</a></p>
</body>

</html>


Control the letters in a text
<html>
<head>
<style type="text/css">
p.uppercase {text-transform: uppercase}
p.lowercase {text-transform: lowercase}
p.capitalize {text-transform: capitalize}
</style>
</head>

<body>
<p class="uppercase">This is some text in a paragraph</p>

<p class="lowercase">This is some text in a paragraph</p>

<p class="capitalize">This is some text in a paragraph</p>
</body>

</html>




Font

Set the font of a text
<html>
<head>
<style type="text/css">
h3 {font-family: times}
p {font-family: courier}
p.sansserif {font-family: sans-serif}
</style>
</head>

<body>
<h3>This is header 3</h3>
<p>This is a paragraph</p>
<p class="sansserif">This is a paragraph</p>
</body>

</html>


Set the variant of the font
<html>
<head>
<style type="text/css">
p.normal {font-variant: normal}
p.small {font-variant: small-caps}
</style>
</head>

<body>
<p class="normal">This is a paragraph</p>
<p class="small">This is a paragraph</p>
</body>

</html>


All the font properties in one declaration
<html>
<head>
<style type="text/css">
p
{
font: italic small-caps 900 12px arial
}
</style>
</head>

<body>
<p>This is a paragraph</p>
</body>

</html>




Border

Set the style of the four borders
<html>
<head>
<style type="text/css">
p.dotted {border-style: dotted}
p.dashed {border-style: dashed}
p.solid {border-style: solid}
p.double {border-style: double}
p.groove {border-style: groove}
p.ridge {border-style: ridge}
p.inset {border-style: inset}
p.outset {border-style: outset}
</style>
</head>

<body>
<p class="dotted">A dotted border</p>

<p class="dashed">A dashed border</p>

<p class="solid">A solid border</p>

<p class="double">A double border</p>

<p class="groove">A groove border</p>

<p class="ridge">A ridge border</p>

<p class="inset">An inset border</p>

<p class="outset">An outset border</p>
</body>

</html>



All the bottom border properties in one declaration
<html>
<head>
<style type="text/css">
p
{
border-bottom: medium solid #ff0000
}
</style>
</head>

<body>
<p>Some text.</p>
</body>

</html>


All the border properties in one declaration
<html>
<head>
<style type="text/css">
p
{
border: medium double rgb(250,0,255)
}
</style>
</head>

<body>
<p>Some text</p>
</body>
</html>




Margin

All the margin properties in one declaration
<html>
<head>
<style type="text/css">
p.margin {margin: 2cm 4cm 3cm 4cm}
</style>
</head>

<body>
<p>This is a paragraph with no specified margins</p>
<p class="margin">This is a paragraph with specified margins</p>
<p>This is a paragraph with no specified margins</p>
</body>

</html>




Padding

All the padding properties in one declaration
<html>
<head>
<style type="text/css">
td.test1 {padding: 1.5cm}
td.test2 {padding: 0.5cm 2.5cm}
</style>
</head>

<body>
<table border="1">
<tr>
<td class="test1">
This is a tablecell with equal padding on each side.
</td>
</tr>
</table>
<br>
<table border="1">
<tr>
<td class="test2">
This tablecell has a top and bottom padding of 0.5cm and a left and right padding of
2.5cm.
</td>
</tr>
</table>
</body>

</html>




List

All list properties in one declaration
<html>
<head>
<style type="text/css">
ul
{
list-style: square inside url('arrow.gif')
}
</style>
</head>

<body>
<ul>
<li>Coffee</li>
<li>Tea</li>
<li>Coca Cola</li>
</ul>
</body>

</html>




Dimension

Increase the space between lines
<html>
<head>
<style type="text/css">
p.small {line-height: 0.4cm}
p.big {line-height: 0.9cm}
</style>
</head>

<body>
<p>
This is a   paragraph   with   a   standard   line-height.
This is a   paragraph   with   a   standard   line-height.
This is a   paragraph   with   a   standard   line-height.
This is a   paragraph   with   a   standard   line-height.
</p>
<p class="small">
This is a paragraph   with   a   smaller   line-height.
This is a paragraph   with   a   smaller   line-height.
This is a paragraph   with   a   smaller   line-height.
This is a paragraph   with   a   smaller   line-height.
</p>

<p class="big">
This is a paragraph   with   a   bigger   line-height.
This is a paragraph   with   a   bigger   line-height.
This is a paragraph   with   a   bigger   line-height.
This is a paragraph   with   a   bigger   line-height.
</p>

</body>
</html>

				
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